Method of and apparatus for water-cooling centrifugal pipe-casting machines.



. D. s. DE LAvAuD.` METHOD 0F AND APPARATUS FO'R WATER COOLING CENIRIFUGAI. PIPE CASTING MACHINES.

RENwEn Aue. 2 7. 191s.

Patented Apr'. 8,' 1919.

PATENT oFricE..

DIMITRI SENSAUD DE LAVAUD, F NEW YORK, N'. 'Y.

METHOD 0F AND APIARATUSFOR WATER-COOLING ENTRIFUGA. PIPE-CASTING MACHINES. I A i l. Specification of Letters Patent.

Patented Apr. 8, 1919.

. Application ledrOctober 5, 1917, Serial No. 194,976. Renewed August 27, 1918. Serial No. 251,693.

" To all whom it may lconcern Beit known that I, DIMrrRI SENsAUD DE LAVAUD, a citizen of the UnitedStates of Brazil, residing at New York city, New York, U. -S. A., have invented new and useful Improvements in Methods of and Ap-l paratus for VVate'r-Cooling Centrifugal Pipe-Casting Machines, of which the yfollowing vis a specification.

This invention relates-tol the casting, of

pipes or other hollow bodies of metal, by

utilizing' centrifugal force.

The object of the invention is to provide a method of and means for quickly and .evenly cooling all parts of the mold of a centrifugal casting machine, so that all pass, butat such a rate and in such volume 4that the water at one part of the passageproper temperature treatment of the mold,V

parts of acomparatively'long casting will be.substantiallyuniformly cooled during the formation of the casting under centrifugal forceandduring the solidiication of the molten`- metal from which the casting is being made; thus making it possible to make better pipes and` to -increase the speed of manufacture.-

Heretofore in the casting of pipes by the centrifugal method, attempts have been made to usel temperature changes to facilitate the production of good castings. Some prior constructions havev provided a large annular water chamber sleeving only a comparatively small part of the pipe mold..

Others have provided water spraying devices; but these have been utterly inadequate for the purpose. Others have provided thin passages through which water is allowed to becomes heated before it can coola part of the mold at another portion of thepassage. It-should be understood that the coling of the elongated pipe mold of acentrifugalmolding machine handling molten metal, is a problem peculiar vto itself and in no way analogous to the cooling of fixed bodiesl or bodies not handling nhot metal in its liquid condition. Some revious- Aconstructions have even attempte very little doubt now, however, that the duringthe formation of the pipe casting, is to cool' the mold and the casting, as quickly and as uniformly -as'possible` 'Iheundersigned hasffdeinonstrated by experiments that very fine results are .obtained when the pipe castthe use. of .temperatureraising devices,vas a line of gas-burners arranged exterior, to the mold; but there ising is quickly and uniformly cooled;'be cause then the rate of cooling may be arranged for in advance, and the casting maybe withdrawn from the mold at a certain predetermined temperature, to Wit, a temy perature equal to the temperature -ofv the molten metal less the degrees of heat ab'- sorbed by the uniformly water-cooled mold, so that the pipe may then be subjected to a higher predetermined temperature, to im'- prove the quality of the casting -to a remarkable degree, as described fully in my copending application, Serial No. 183,503,

filed July 30, 1917.

I have discovered that the rotatingmold of a centrifugal pipe casting machine may b e quickly, adequately, substantially uniformly and controllably cooled, by means of and in all parts, by making the water acket of a- Vcertain minimum thickness, preferably at least as thick as or slightly thicker than the thickness of the wall of the pipe being ca'st, 'while continuously feeding water at the jacket inlet under pressure, .and by pro-v viding a Water outlet or outlets lfor the jacket having a cross-sectional area less than the cross sectional area of the inlet.

In other words, the essence of the present invention is the provision of an annular water jacket of some thickness to sleeve practically the entire length of the rotary mold o f a-centrifugal pipe casting machine, the

vjacket having an always open inlet and outlet (though valves maybe provided to vary the'A relation, between` .the cross-sectional areas of theinlet and outlet), and the con-J tinuous feeding of water to the jacket at the inlet `under sufficient pressure `to predeter- 4minefthat the water :will be maintained in continuouscirculation through the jacket at substantially constant pressure and substantia'lly uniform temperature in all parts of th'e jacket The present invention was partially disclosed, among other things j in an application, Serial No. 131,064, iiled jointly by myself and one Arens, November 13, 1916, and so at this point, opportunity may be taken to explain, to comply with theV patent statute, that certain parts of the structure shown in the drawings hereof, and the inventions illustrated thereby, are more 4fully described and claimed in said application Serial No. 131,064. l

The present invention will be more clearly understood from the followingdescription, when taken in connection with the accompanying drawingillustrating the invention,

in which drawing Figure 1 is a vertical longitudinall section the left-hand end portion of the mold of a machine of slightly different construction than the machine of Fig. 1; and

Fig. 6 is a transverse vertical section taken on the line 6-'6 of Fig. 5. Y A Referring lirst to Figs. 1 to 4, inclusive, a shell 1,preferably made in sections, is

Y suitably supported, as upon legs 2; a rotary mold 3 is disposed within this shell, preferably carried upon the ball-bearings 51.

The annular space between the `mold 3 and the shell 1 is provided for a water jacket, 52,

fvater in the jacket being kept lcontinuously 1n circulation under suitable pressure as described herein in accordance w1th the invention. The water under pressure is in the present case admitted at aV single inlet .through the pipe 4 centrally located at the bottom of the shell. The water after cooling the mold passes from the machine by way of pipes 53 which may conveniently be located in the legs 2. Near each end of the mold 3 where the water leaves 'the water jacket chamber 52 are providedvanes 26 on Y the-mold 3 and vanes 27 on the shell 1, forming a turbine, so that as the water is forced to circulate toward the pipes 53 the water acts upon these vanes 26 and reacts upon the vanes 27 to cause rotation of the mold.

According to thls construction, the crosssectional area of the inlet'from the pipe 4 is made so much larger-than the cross-sectional area ofthe space between the vanes' 26\ that, dueallowance being made for'the resistance to theV circulation `of the wate'l eX- erted by the work done by the water in actuating the turbine, the Water kept continuously circulating in the water jacket chamber 52 is maintained under the proper `pressure pursuant to the invention. In order thatithis pressure may be varied at the water inlet, the pipe 4 is provided with an adjustable valve 80.

In'Fig. 1,l the casting is indicated at T; as also in Figs. 3 and 4. It will be noted from Fig. l that the thickness of the water jacket chamber is over twice as great as. the thickness of the pipe wall; and itis believed that best results are obtained when the thickness of the water jacket is at least as thick vas the pipe wall of the pipe being molded in the rotating mold.

he maintenance of the circulation in the water jacket under pressure is of the essence of the present invention. mold is rotating, and it is thereby moving its entire surface relative to the Water' in the Although the jacket, this is not enough, as we have'found that there is one part of the mold which lis hotter than any other. This isthe line, parallel to the axis of the mold, along which the metal is first poured. At the instant the metal is poured, steam forms itself on the outside of the mold, opposite' the line along which the poured metal first hits the -inside of the mold; and the adherence of the Water to the mold, as this term may be used for Want of a better one,'is not absolute, but relative, that is, is not'uniform. It has been observed that if an iron plate has :thrown on it a little water, a portion of the water next to the plate will not vaporize immedi- 1 ately; it will form itself into little globules of water, which will begin to dance on the hot iron plate. The explanation of this isA that as soon as the water comes into contact with the hot plate, a 'certain quantity 'of steam forms itself between the iron and the water, which has the effect observed. The same phenomenon, I have discovered, is present in the case ofthe exterior surface of the mold of a centrifugal pipe-casting ma.- chine, occurring opposite the hotter longitudinal subdivision of .the mold which irst receives the metal. Unless the steam formation is suppressed so, promptly and adequately that in effect lit really never commences, serious difficulties arise. If the steam formation occurs along a particular portion of the mold, thus preventing the mold from being completely surroundedA by water at every point, the mold contracts and expands at-diiferent-portions different [amounts and fatal distortion takes place. I

have discovered thatthe steam formation may be suppressed, by maintaining the Water in the jacket continuously in circulation, under pressure. The circulating water l,under pressure tnenexerts equal pressure against all parts of the mold, and suflicient pressure at the zone of possible steam formation, to throttle the formation of steam at messie any point. No steam being formed, the condensation of this steam is not a problem. The entire mold from end to end is uniformly and adequately cooled, distortion of the mold cannot occur, and the casting is kept at an even `temperature in all parts, thereby assuring that the casting will be flawless and may be subjected to a later heat treatment, if desired, depending on the temperature of the casting when removed from the mold, Such a heat treatment, as mentioned above, isexplained in my certain c0- pending application, iled- July 30, 1917, Serial No. 183,503.

Referring now to 1 which houses the rotating mold 3, to provide the water jacket chamber 52, is provided with an -open-bottomed hood 81, to the left of the left-hand end of the water jacket, for containing a plurality' of buckets 83 circumferentially arranged on the left-hand end of the rotating mold 3.

4 the-buckets to drive xthe rotating mold. The

manually adjustableball valve 87 is provid- Ved so the cross-sectional area of the large end of the nozzle 86 maybe varied at will. 'This end of the nozzle may be considered the outlet of the water jacket circulation.' In

view of the fact that such a variable outlet a valve similar to the valve omitted from the inlet to It will be noted that in is provided,

pressure in the chamber 52is controlled by a valve in the inlet (the valve 80 in the pipe 4) the cross-sectional area of the outlet, that is, the

' turbine 26-27, beingl practically constant.

, in the water jacket v and controlling 'the pressure In the case of the construction of Figs. 5 and 6,'i t willl be noted that the water is not used for doing the work of rotating the; mold 3 until it has passed `beyond a variablev outlet arrangement, 'and so the inlet, or in other wordsfthe pressure at the cross-sectional xarea of the inlet, may be maintained practically constant; reliance being placed uponithe ,valve 87 for adjusting under which 'the circulating water is maintained during.

operation ofthe machine.v It will of course be'understood that in carrying out the in-- vention the velocity of; the circulating water need not necessarily be employed to dothe `work of rotating'the mold 3; andv in such case adjustable valves may I'be placed inv either the inlet orthe outlet or in both. In

l,mold having a length than its maximum wid-th,a shell extending Figs. and 6, the casing In this -construction, as in the construction of Fig. 1, the cooling Athe combination comprising a rotary mold the inlet.

I claim:

1. In a centrifugal casting machine, the combination comprising an elongated rotary several times greater circumferentially around said mold and arrangedto form a chamber for the circulation of cooling liquid extending 'substantially from end tb end of the mold, and means for maintaining the chamber full of cooling liquid under pressure.

2. In a-centrifugal casting machine, the combination comprising an elongated iotarv mold having a lengthA several times greater than its maximiun width, a shell extending circumferentially around said mold and arranged to form a chamber for the circulation of cooling liquid extending substantially from end to end of the mold, andl means for maintaining the chamber full of cooling liquid under pressure in circulation, such means comprising a continuously open yinlet and outlet and a valve in one of said inlet or outlet for varying the relation between'the cross-sectional areas of the inlet and outlet. n 'A 3. `In a centrifugal casting machine, the combination comprising an elongated rotary mold having a length several times greater than its maximum width, a shell extending circumferentially around said mold and ar ranged to form a chamber for the circulation of cooling liquid under pressure e- ,t'ween said mold and shell, means for maintaining the chamber full of cooling liquid under pressureA and in circulation. andl means for. controlling the flow ot' liquid to' maintain the mold at a substantially constant temperature.

4. In a centrifugal pipe casting machine,

ioo

having. a length several times greaterthan its maximum width, a shell extending cir,- cumferentially around saidmold and arranged to form achamber for the circulation of cooling liquid extending substan-V tially from end to end of the mold, and means for maintaining the chamber full of cooling liquid under pressure, said cooling chamber having a thickness at least as great as the wall 'thickness-of the pipe cast by the machine. *i A 125 5. In a centrifugal pipe casting machine, the combination comprising a rotary mold having a length 4several times greater than L' its maximum width, a shell extending-cir` cumferentially laround said Amold and .'ar- 130 ranged to form a chamber for the circulation of cooling liquid extending substantially from end to end of the Vmold, and means for maintaining' the chamber full of cooling liquid under pressure, said cooling chamber having a thickness approximately twice as great as the wall thickness of the pipe cast by the machine.

A6. In a centrifugal casting machine, the combination comprising an elongated rotary mold having a length several times greater than its maximum Width, a shell extending circlunferentially around said mold and arranged to vform a chamber forthe circulation of cooling liquid extending substantially from end to end of the mold, and means for maintaining the chamber full of cooling liquid under pressure` said means including an-inlet and an outlet so designed that the velocity of the liquid issuing from the outlet is from ten to forty times as great as the velocity of the liquid liowing in at the inlet.

7. In a centrifugal pipe casting machine, thecombination comprising al rotaryA mold having a length several times greater than its maximum Width, a shell extending circumferentially around said mold and arranged to form a chamber for the'circulation of cooling liquid extending substantially from end to end of thev mold, and

.means for maintaining the chamber full of cooling liouid under pressure, said cooling chamber having a thickness at least as great as the wall thiclmess of the pipe cast vbythe machine, and said means including an inlet and an outlet of suchrelative dimensions that the velocity of the liquid issuing from the outlet may be from ten to forty Atimes` as great as the velocity of the liquid flowing in at the inlet.

8. In the art of centrifugall casting pipe i and other hollow articles, t e process of cooling the rotary mold during casting, which consists in confining and guiding a flow of cooling liquid in contact with the surface of the mold opposite to the surface receiving the molten metal, while maintaining the liquid under pressure greater than `cooling an elongated rotary substantially and other hollow articles, the

t e pressure required to circulate the same.

9. In the 'art of'ce'ntrifugallyv casting pipe rocess of cooling an elongated rotary su s tantially cylindrical mold during castlng, which consists in confining a flow of cooling liquid under pressure in an annular sheet from end to end of the elongated mold and guiding the same in contact with the exterior thereof. 10. In the art of centrifugally casting pipe and other hollow articles, the process of cylindrical mold during casting, which consists in connlng a flow of cooling liquid unjniold at ture.

*cooling an elongated rotary substantially cylindrical mold during casting, which consists in confining, a flow of cooling liquid under pressure in an annular sheet from end to end of the enlongated mold and guiding the same in contact with the exterior thereof, the cooling liquid being thus confined and guided for contact wlth the exterior of the mold at a certain velocity, and being released from said confinement after contact with. the exterior of the mold at a velocity from ten to forty times as great as the first-mentioned velocity.

12. In the art of centrifugally casting pipe and other hollow articles, the process of .cooling han', elongated rotary substantiallythe same in contact with the exterior there-A of, the annular sheet being at least as thick as the wall of the pipe belng cast, the coolingliquid being thus confined and guided for contact with the exterior of the mold at first-mentioned velocity.

13. In a centrifugal casting machine, the combination comprising an elongated rotary mold the length of which is several times its Agreatest width, a shell extending circumferentially around said mold and arranged to vform-a chamber for the circulation of cooling liquid under pressure between said mold 'and ishell, means for maintaining the chamber full of cooling liquid under pressure and in circulation, and means' for con- Aa certain velocity, and being'released from vsaid confinementl after vcontact with the exjterior of the mold at a velocity from ten to -forty times, approximately, as great as the1 trolling the flow of liquid to maintain the 14. In the art of' centrifugally casting pipe and otherY hollowarticles, the process of cooling an elongated rotary Substantially lcylindrical mold during casting, which consists in confining a ow., of cooling liquid in an annular sheet from endv to end of the elongatedmold and guiding the same in cona substantially constant temperatact with the exterior thereof, while controlling the flow of liquid'to maintain the mold at a substantially constant temperature.-

In testimony whereof I have signed my name to this specification. DIMITRI SENSAUD DE LAVAUD. 

